Technologically-advanced versions of melee weapons are a favorite motif of space operas, video games, and science fiction RPGs. Lightsabers, basically uber-tech swords, are probably the single most famous example, and are detailed in their own article linked to at the bottom of the page. This article documents how technological enhancements can be used to better other kinds of cutting weapons. "Energy blades" (such as Halo’s Type I Energy Sword or the Sunsword from Thundarr The Barbarian) and the like are considered variants on the lightsaber and won’t be addressed here.

The generic term ‘blade’ is used here for many types of cutting weapons, and could refer to knives, swords, machetes, or any other commonly used cutting configurations. The high-tech enhancements discussed can usually be applied to any variation of these.

The practicality of high-tech melee weapons in an age of ever more sophisticated firearms is nebulous at best. Real life combat experience in close quarters, such as that engaged in by the military in urban combat and by inner-city police forces, will attest that pistols are almost always preferable, and melee weapons are used only in certain specialized circumstances such as stealth missions, or when firearms aren’t available. Most of the weapons discussed below would be considered niche weapons, very useful in certain specific applications but less so in general combat.

ELECTRIFIED BLADES
Tech Level: 10

Low-powered versions of electrified swords already exist, used in the sport of fencing to register critical hits on a participant. A knife-like weapon called the Shocknife is also available. A combat-ready version would be much more potent, more of a cross between a taser and a normal bladed weapon, with a high-voltage electrical charge running through the metal of the blade. The blade may have to be specifically configured, such as having two narrow, parallel cutting edges, in order to optimize the delivery of the electrical charge.

Both the handle and hand guard would have to be made of tough, non-conducting material, and the handle would hold the weapon’s power cells. Having the weapon’s wide electrical blade constantly charging when out of its sheath would be dangerous for a number of reasons (not the least of which it could spontaneously discharge onto the user) and would also drain the power cell too fast. So, more practically, the electrical charge would only be activated by the user by a switch on the handle, preferably just before or at the moment the blade makes contact with its target.

The practical use of such weapons is questionable, at least against normal human targets. Most people, even armored soldiers, can usually be stopped just as well by either a well-placed knife thrust or a taser separately, so the need for a combined weapon seems superfluous. However, the makers of the Shocknife claim the weapon is useful as an intimidation tool—even casual contact with the knife will make potential opponents think twice about engaging with the wielder. This may indeed be the case. Electrified blades’ most practical use, however, may be against creatures who are not normally intimidated, or even slowed down, by bladed weapons, such as bears, mountain lions, and so on. In science fiction settings, these may include alien creatures as well as enhanced humans.

Combat chainsaws and power saws are the darling of gamers everywhere, whether it be tabletop or video gamers, whether the foe be powered armor troopers, vicious alien monsters, or drooling zombie hordes.

However, as cool as games make them out to be, chainsaws as they currently exist would have a number of real-world drawbacks as weapons. They’re heavy and clunky to wield, are very loud, and are subject to kickback and broken chains. In order to be made effective as weapons, they would have to be modified in a number of ways.

First and foremost, their gasoline motors would have to be replaced with high-performance electrical engines, and these in turn would require a more potent, compact mobile power source than is currently available. The switch to an electrical motor would also solve some of the noise problem. They would also have to be made of stronger, more lightweight materials to make them less vulnerable to breakage and stops that result in throwback, such as advanced composites or carbon nanotubes. Finally, a reconfiguration of their operating components may be necessary in order to make them more balanced and easy to use by the common wielder.

However, even so, they would still likely be somewhat clumsy devices impractical for most combat uses. Most of what they can do can be accomplished by other devices and weapons, usually cheaper and more easily. So what would their killer app be, so to speak?

The simple answer would be as anti-armor measures. Advanced ballistic armors, both today and the future, are not just effective at stopping projectiles but also at stymieing most types of cutting weapons as well. A chainsaw or powered saw would alter that equation, allowing the user to cut through an enemy’s armor that would otherwise stop bullet and knives. Ideally the saw would be aimed at weak spots in the armor, such as joints, to allow penetration as quickly as possible.

In the tabletop wargame/RPG Warhammer 40,000 and in the video game franchise Gears of War, combat chainsaws see what is probably their most practical usage--as bayonet-like tools on the end of heavy rifles, designed to penetrate enemy personal armor during close combat. The wielders’ strength-enhancing powered armor also makes large, sword-like versions practical in the WH40K setting.

In Japanese anime, large mecha are also occasionally seen using chainsaw-like blades, such as in the anime series Full Metal Panic.

MOLECULAR EDGED WEAPONS
Tech Level: 12

These are cutting weapons with their blades pre-sharpened to an edge that’s only a few molecules wide, or smaller. They would be supremely sharp--many times that of a new razor blade. Today, some real-life molecular edged tools are in use for highly specialized fields such as surgery. Diamond knives have edges barely 20 nanometers wide (compared to the absolute sharpest metal blade, whose edge is over 200 nanomateres wide.) However, these don’t have the robustness or toughness to be wielded as combat weapons. Molecular-edged weapons are a favorite motif of cyberpunk settings such as Shadowrun, where they are often used to create enchanced katanas and wakizashis.

One problem with creating molecular-thin edges is that the materials used to make normal knives and swords, steel and its various alloys, are not conducive to holding such thin structures. Even if they can be sharpened to that degree, the edge quickly break or wear away. The solution is to make the entire blade out of materials that can hold such an edge, such as silicate composites or carbon nanotubes, or to use a blended materials technique where most of the blade is one type of material, such as carbon steel, but where the cutting edges are another type of material anchored to the main blade metal, such as diamond.

These techniques, however, have never been applied to very large cutting surfaces such as knives and swords, and could prove to be prohibitively expensive. Yet as technology progresses and artificial materials such as manufactured diamonds and carbon nanotube become cheaper and more readily available, this may change.

The main advantage of molecular edged knives over normal, merely sharp knives will mostly be in penetrating light armor, especially in thrusting attacks. In the science fiction settings these are most often seen, such as cyberpunk worlds, they would also be unusually effective against the metal and ceramic parts of cybernetic-enhanced inhabitants.

VIBRO BLADES
Tech Level: 13

We’re all familiar with electric carving knives, and some surgical bones knives which vibrate enough to cut through stiff materials such as bone, but which will leave more flexible surfaces, like human skin, untouched.

A vibro blade, another weapon with a long history in various science fiction sources such as Star Wars’ Expanded Universe, works on a similar principle. The blade of the weapon is attached to an advanced, high-performance motor in its handle, which vibrates the blade at extremely high speed. These vibrations are similar to small but rapidly repeated sawing motions, allowing the blade to slice through most normal materials quickly and easily. Vibrations may be measured in hundreds or even thousands of cycles per second, depending on the sophistication of the weapon.

The faster the vibrations, the more cutting power the blade will have, but also the harder it will be to wield and the quicker the blade will wear down. In fact, hand fatigue may be a serious consideration when handling these devices, similar to holding a modern day power handsaw while it cuts through tough material. Even with vibration-reducing handles and gloves, the muscles of the hand eventually become overly fatigued, and the weapon may end up being involuntarily dropped. Given that the wielder how potentially dangerous these weapons can be to an unprotected user, that could be very bad news indeed.

Vibro blades may be combined with molecular edges to make them truly formidable weapons. However, even diamond-edged blades will wear down relatively quickly if employed on these devices.

Vibro blades may be more useful as utility cutting devices rather than dedicated-purpose weapons, and used in combat only if other, more effective weapons are unavailable. However, they could be deployed bayonet-style on the end of rifles to use against armored enemies if combat happens to become close and personal.

FORCE FIELD BLADES
Tech Level: 21

Force field knives have appeared in various works by Isaac Asimov and in the tabletop RPG Gamma World (where they are ironically called vibroblades.) The Asimov version is occasionally rumored to be the original inspiration for the lightsaber.

When turned off, the force field blade seems like an empty knife hilt, much like a deactivated lightsaber. When activated, however, the force field generator within the handle creates a force field shaped like a knife’s or a sword’s blade. The edge of this force field blade can be made far sharper than even the keenest molecular edge, tapering down even smaller than individual atoms, and the blade itself is frictionless or nearly so. This would allow the weapon to slice through almost any normal matter with ease. Unusual barriers, such as ultra-tensile strength materials, electrically charged surfaces, or other force fields, may slow down or stymie the blade altogether. If the blade encounters too much resistance, or absorbs too much energy, the blade may collapse and the generator overload.

The force field blade may or may not be visible to the human eye, depending on its design and exactly how force fields work in a particular setting. Invisible blades may be oriented along the configuration of their hand guards for their wielders’ convenience.

The nature of the force field used (see the article on force fields, linked to at the end of this page) may affect how the weapon handles and the type of damage it does. For example, electron-based force fields may also deliver an electrical shock to its target even as its slicing through it.

Like with most of the weapons discussed in this article, force field blades would only have limited conventional combat usefulness, especially at upper tech levels that would be dominated by far more potentially devastating weapons technology. Like vibro blades, they would more useful as a general cutting tool, and pressed into use as a weapon only if necessary. Asimov’s version was used most prominently as a concealed weapon for covert police work and espionage missions.